Joanna Jarmolowska, Marcello Turconi, Pierluigi D’Antrassi, Pierpaolo Busan, Piero Paolo Battaglini
B.R.A.I.N. Center for Neuroscience, Department of Life Sciences, University of Trieste, Italy
A Brain Computer Interface (BCI) is a device that accepts commands contained in neurophysiologic signals, without using the explicit output pathways of the brain. This can allow paralyzed people to create new communication channels. As a matter of fact, every year thousand of people lose the use of the output pathways of the brain with loss of their ability to communicate. Recent studies, however, have shown that patients can learn to control the amplitude of EEG activity in specific frequency bands over sensorimotor cortex and use it to control an output device. Movement or imagination of movements are accompanied by decrease in mu/beta activity; conversely, rhythm increase occurs in the post-movement period and with relaxation.
We adopted a focal Event Related Desynchronization/Synchronization paradigm of two or more mental states in healthy subjects, elaborated by a specific hardware, to move a cursor on a screen until it touches a predicted target with a user-friendly and economical BCI. We implemented the BCI2000 software as platform for human-BCI in order to extract the feature components of the EEG signals and to use them in CursorTask. The EEG signals were recorded with a MICROMED portable amplifier. Both the screen and the data acquisition device have been interfaced with a laptop computer running BCI2000. We are also developing dry electrodes which, besides avoiding the use of conductive gel, allow the application of electrical filters close to the EEG source with the aim of impairing the signal-to-noise ratio.
Keywords: BCI, sensorimotor cortex, EEG, dry electrodes